Eyeworld

EW FEATURE 46 Refractive surgery in military personnel and first responders • July 2016 AT A GLANCE • Some concerns in military refractive procedures relate to the risk of flap dislocation, particularly using microkeratomes. However, femtosecond flaps have been shown to be very effective. • The prevalence of PRK and LASIK varies among the different branches of the military and also among hospitals in the same branch. • There are certain requirements and postop considerations for pilots who have had refractive surgery. They undergo a process after surgery to demonstrate their vision is good enough to return to flying. by Ellen Stodola EyeWorld Senior Staff Writer military, but as studies and experi- ence have demonstrated safety and stability even in extreme environ- mental situations, most of these re- strictions have been lifted," he said. "LASIK, for example, was restricted for certain aviators in the Air Force until we were able to demonstrate in altitude chamber studies that vision was stable up to 35,000 feet." Dr. Caldwell noted that there are still occupational considerations, but for LASIK and PRK most of the restrictions have been lifted. For ICLs, he said, where there is less history, there are still restrictions for some fields such as aviation, and it is disqualifying for patients who had the surgery before deciding to join the military. To be eligible for refractive surgery in the Navy, personnel must Dr. Stolldorf said these options are used sparingly. "We tend to use this technology in patients with significant refractive errors who are not candidates for PRK or LASIK," he said. "This technology is not approved for certain warfare com- munities, such as aviation." Dr. Stolldorf said that if he puts an ICL in a person who flies for the Navy or Marine Corps aviation, they will no longer be able to fly profes- sionally, even if they see 20/20. Eligibility Today, eligibility for refractive sur- gery in the military is based mostly on whether or not patients are good medical and surgical candidates for the procedure, Dr. Caldwell said. "In the past, there were a number of occupational restrictions in the eye where a flap actually came up." These were generally in cases of trau- ma that would have damaged the eye regardless of the history of re- fractive surgery, Dr. Caldwell added. Dr. Stolldorf said that, in his experience at the Naval Hospital Camp Lejeune, femtosecond LASIK is used often. Integration of LASIK in the Navy was delayed in the past be- cause of fears of flap dislocation, he said. "Mechanical microkeratomes are not used in the military precisely because [the flaps] are feared to be less stable in a stressful environ- ment, such as an explosion or ejec- tion from a fighter jet." Although mechanical microkeratome flaps require a waiver for military service, Dr. Stolldorf said that it is preferred that applicants and active duty service members have either PRK or LASIK with a femtosecond flap. Prevalence of PRK and LASIK in the separate branches The ratio of PRK vs. LASIK can vary. This is different not only among branches of the military, but also from center to center in each branch based on the needs of the patient population at each base as well as on individual surgeon preferences, Dr. Caldwell said. "In general, the Navy has tended to do a higher percent- age of LASIK than the Army and Air Force," he said. Dr. Stolldorf stressed the preva- lence of PRK vs. LASIK among Naval hospitals. These hospitals serve the Navy and Marine Corps bases, he said. Most centers do more PRK than LASIK, he said, but in 2 hospitals, Naval Medical Center San Diego and Naval Hospital Camp Pendleton, LASIK cases outnumber PRK cases. Phakic IOLs Dr. Caldwell said that phakic IOLs, specifically ICLs, are used in the Army and Navy for patients with high myopic refractive errors who would not otherwise be good candi- dates for corneal refractive surgery. However, ICLs are not currently approved in the Air Force, he added. "These cases make up a smaller percentage of the total refractive surgery performed in the Depart- ment of Defense, however, these are frequently the patients most debilitated by refractive error and the patients who benefit the most," Dr. Caldwell said. Additional considerations are needed for military refractive surgery patients R efractive surgery requires careful patient selection, and refractive surgery in the military requires extra considerations, as there are particular concerns and proce- dures for performing these surgeries in the different branches of the mil- itary. Colonel Matthew Caldwell, MD, San Antonio, and Lt. Cmdr. Hunter Stolldorf, MD, department head, ophthalmology and refractive surgery, Naval Hospital Camp Le- jeune, Jacksonville, North Carolina, weighed in on possible concerns for refractive surgery in the military and other considerations that should be noted. LASIK in those at risk for ocular trauma "There certainly is a concern about the potential risk of trauma in LASIK patients, especially due to the fact that these patients can potentially incur the injuries while deployed in austere locations distant from an ophthalmologist," Dr. Caldwell said. "Fortunately, the actual incidence has been very low." However, he noted that this is something that is closely followed. "Of the tens of thousands of femtosecond LASIK flaps, there have only been about 5 or 6 cases in the Department of Defense of trauma to a post-LASIK Refractive surgery and patient selection in the military Refractive surgery options within the Army C olonel Scott Barnes, MD, chief, U.S. Army, Warfighter Refractive Eye Clinic, Fort Bragg, North Carolina, said that the breakdown of LASIK and PRK within the Army is about 70% surface ablation and 30% LASIK, although he noted that it can vary widely depending on the location. About 5 years ago at Dr. Barnes' hospital, this number was nearly 100% surface ablation. Now, there are roughly 55–60% LASIK cases. As for phakic IOL use, Dr. Barnes said that these are "a fantastic option for the right patients." However, he noted that it's not something that's offered to everyone. It's a little different than in civilian clinics, he said, because the Army has a large number of young patients, who may be in their early 20s or younger. Looking at those young patients, it's not uncommon for them to have some topographic irregularity in the cornea. Although that's not necessarily concerning, it may indicate the beginnings of keratoconus in younger patients. ICLs have opened up the options for young patients who may have to wait for some years to be sure the corneal irregularities are not progressing if they want to consider laser surgery, Dr. Barnes said. Those who have previously had a phakic IOL are currently disqualified from entering military service, Dr. Barnes added. These patients have the potential for future issues such as retinal detachments and other vision concerns, and their pre- and postoperative records are often unavailable. "One of the biggest things that I remind people is that for us in the Army, this is not a cosmetic program," Dr. Barnes said. The bottom line, he said, is that we're asking these soldiers to do the country's bidding and this could involve tough situations with tough people who may wish to do our soldiers harm. If you can't see them before they see you, that could put your life on the line. It's an amazing thing for soldiers to be free from glasses or contacts, Dr. Barnes said. "We don't want people in the military to have to face [a situation] where they can't tell if someone approaching them is a friend or foe." Editors' note: Dr. Barnes does teaching and physician certification for Abbott Medical Optics (Abbott Park, Illinois) and STAAR Surgical (Monrovia, California). Contact information Barnes: scott.d.barnes.mil@mail.mil

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